Sorry to be so long with a reply, but I usually don't look at these threads. It has been so long since you asked the question, I hope you have not quit looking in the forum for an answer.
I was there for three days a couple of years ago. My wife had a seminar to attend and I spent the days wandering around by rail.
Getting around by rail in South Korea is really easy. You can get a schedule book at the main railroad station in Soeul, and probably a few other places as well. It has the station names, or at least the main ones in English as well as in Korean. I have a two or three year old copy at home. email me and I can give you the specifices as it was at that time. There is also now a high speed link across the country more or less Seoul to Busan.
The high speed line is French TGV equipment. The rest of the system is mostly diesel cars, diesel push-pull train sets, or locomotive hauled coaches. The locos and coaches look very American. The system is all standard gauge. Tickets are reasonably priced. Soeul also has a very extensive subway system.
Don't know your exact in-town destination, but there are buses from the airport into town that are very conveniet to many destinations. We took one that dropped us off within a few steps of our hotel door.
George
